To provide large numbers of condiment sachets in high-speed operations, sachets may be formed in continuous or intermittent processes wherein sealing and cutting operations are performed on two webs of laminated material to form, fill, and seal individual rectangular sachets. Several sachets may be formed, filled, and sealed simultaneously and in parallel, e.g., in an 8-across, 10-across or 12-across configuration. Means to facilitate tear initiation, such as V-notches or edge cuts, may be provided simultaneously or in separate, post-forming operations. Some sachets include means to help control propagation of tearing after initiation, such as a perforation. In some cases, means may be provided to facilitate removal of a corner of the sachet.
Potential Issues that may affect consumer satisfaction levels with ketchup sachets commonly used in fast-food restaurants in the United States include: (1) difficulty directing ketchup with sufficient precision onto a desired area of a food item or dipping location; (2) undesirably high flow rates, which may result in dispensing excessive amounts of ketchup; (3) undesirably low flow rates, which may result in frustration with the time required to dispense an optimal volume; (4) difficulty in dispensing ketchup from certain regions of the sachet, e.g., corner areas; (5) undesired expulsion of ketchup from the sachet immediately upon opening, in some cases resulting in ketchup being displaced from the sachet onto fingers, clothing, a restaurant table, or other undesired locations; (6) difficulty in tear initiation; (7) esthetic issues such as irregularities in configuration; and (8) tendency of the sachets to tear in unexpected directions in response to manual opening force, e.g., opening of a longitudinal side seal. These issues are related in part to differences in the sizes and configurations of consumers' fingers, and differences in the magnitude and direction of forces that consumers may apply during use of the sachets, but also to concerns with the sachets themselves.
Beyond the above-discussed consumer satisfaction/performance issues, additional design and manufacturing issues include: (1) the tendency of certain varieties of ketchup to react with packaging materials over time, resulting in leakage and/or other problems if the ketchup is not hermetically sealed within an interior layer of suitably corrosion-resistant material, (2) the need for the packet to have suitable oxygen barrier, moisture barrier and other properties to protect the ketchup from deterioration so that the ketchup remains fresh for a period of several months, and (3) selection of design parameters that enable the sachet to contain a desired volume of product without bursting or leaking during manufacture, storage, transportation and use, without using excessive amounts of packaging material. The sachets need to be capable of withstanding bursting forces associated with significantly decreased exterior pressure if they are to be used for airline meals, or if they are to be transported at high elevations between manufacturing locations and their ultimate destinations. Also, the sachets should be able to withstand dynamic forces associated with handling during which the sachets may contact each other while tumbling or otherwise moving relative to each other, without inadvertently tearing open due to such contact.
Some of the same or similar issues can be encountered with sachets for other condiments such as, e.g., mustard, mayonnaise, honey, syrup, cream cheese, jam, jelly, sweet relish, tartar sauce, hot sauce, barbecue sauce, steak sauce, cocktail sauce, taco sauce, salad dressing, mint sauce, soy sauce, horseradish sauce, lemon juice, and vinegar.
Spouted sachets having narrow dispensing spouts can be helpful in addressing some of the above issues, e.g., controlled tearing during opening, and consumers' regulation of dispensing directions and volume flow rates. However, known spouted sachets have significant drawbacks. For example, with certain varieties of ketchup which may be characterized as having very high viscosity, and being non-Newtonian, thixotropic fluids, designing spout dimensions that enable efficient use of packaging material while also providing acceptable flow rates under widely varying conditions can be challenging. Various consumers may apply widely varying pressures over widely varying areas of the sachets during use, and the sachets may be used at widely varying temperatures, e.g., at outdoor events in cold weather such as football games, where the sachets may be at temperatures below 32° F., or at outdoor events in hot weather such as baseball games, at temperatures above 90° F. Further, with certain condiments, inclusions or thickening of fluids over time may impede flow to varying degrees, resulting in inconsistent dispensing performance. Also, the ratio of product volume to packaging material in spouted sachets may be significantly lower than for simple, rectangular sachets of similar sizes, which may create a need for improvements in sachet design and manufacturing processes to decrease costs. Another issue with some spouted sachets is that similar sachets may have different flow characteristics if their lines of weakness are positioned at slightly different locations relative to a tapered dispensing spout, leading to consumer dissatisfaction due to inconsistent performance related to significant differences in the sizes of their dispensing openings. Also, providing sachets in which the spout is consistently centered can be challenging. Where multiple sachets are formed, filled and sealed simultaneously from webs of film, spouts along one side of the operation may be off-center in one direction while spouts on the opposite side are off-center in the opposite direction.
Another issue with production of spouted sachets is that they tend to have larger sealing areas. This may result in a greater likelihood of droplets or other small quantities of a food product dripping onto seal areas from filling tubes during high speed commercial form-fill-seal operations, resulting in the small quantities of food product being trapped between front and back walls of the sachets or packets in seal areas as the seals are formed. When adapting form-fill-seal equipment to change from production of non-spouted sachets to production of spouted sachets, greater force may be required to apply adequate sealing pressure to the larger seal areas of the spouted sachets. This can result in strains on equipment components, and can result in difficulties in maintaining the precision required to consistently and reliably form sachets or packets that meet desired quality standards at desired rates of production.
There is a need for improved, filled sachets that address the above-identified issues, and a need for improved methods of making such sachets efficiently at competitive price points in high-speed commercial mass production.